Vocabulary of a Circle

Vocabulary of a Circle

• Circle

• Perimeter

• Circumference

• Pi (π)

• Diameter

• Radius

• Area

Area

The number of square units needed to cover a region.

Circle

A closed two dimensional figure having all points the same distance from a point called the center.

Perimeter

The distance around the figure . The perimeter is found by adding the lengths of all of a polygons sides.

Circumference

A circumeference is the perimeter of a circle

Pi

 $\left(\pi\right)$  

π—is the ratio of the circumference of any circle to the diameter of that circle. In decimal form, the value of pi is approximately 3.14

Diameter

A line segment that has passes through the center of a circle and that has endpoints on the circle.

Radius

A line segment that has one endpoint that is the center of a circle and another endpoint that is a point on the circle.